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arXiv · 0806.3719

Accurate determination of tensor network state of quantum lattice models in two dimensions

H. C. Jiang·Z. Y. Weng·T. Xiang
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Abstract

We have proposed a novel numerical method to calculate accurately the physical quantities of the ground state with the tensor-network wave function in two dimensions. We determine the tensor network wavefunction by a projection approach which applies iteratively the Trotter-Suzuki decomposition of the projection operator and the singular value decomposition of matrix. The norm of the wavefunction and the expectation value of a physical observable are evaluated by a coarse grain renormalization group approach. Our method allows a tensor-network wavefunction with a high bond degree of freedom (such as D=8) to be handled accurately and efficiently in the thermodynamic limit. For the Heisenberg model on a honeycomb lattice, our results for the ground state energy and the staggered magnetization agree well with those obtained by the quantum Monte Carlo and other approaches.

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H. C. Jiang, Z. Y. Weng, T. Xiang. 2008-06-23. Accurate determination of tensor network state of quantum lattice models in two dimensions. https://doi.org/10.1103/physrevlett.101.090603

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